Catholic bishops in Christchurch say they have already apologised to a victim of alleged abuse who has written a book called Say Sorry.

Ann Thompson's book, which goes on sale on Monday, tells of physical, mental and sexual abuse she suffered as a child at St Joseph's Catholic Orphanage for Girls and Nazareth House in Christchurch.

Now aged 68 and a Christchurch mother of three, Thompson told the Press newspaper she had written the book "so the Catholic Church would come forward, admit this has happened and apologise".

She claimed she was thrashed regularly at Nazareth House and nuns would shove her head down the toilet because she was born out of wedlock.

This week, she said that although some members of the church would remain in denial about her claims, she was confident they would be believed by others once they had read the book, a Penguin publication.

But the Catholic Bishop of Christchurch, Barry Jones, said yesterday that both he and and his predecessor, John Cunneen, had apologised to Thompson on separate occasions.

Bishop Jones said the Christchurch diocese participated in mediation in 2001 between Thompson and the religious orders responsible for the orphanages.

"Everyone, including Mrs Thompson, signed up to indicate their satisfaction with the terms of the settlement," he said.

The Press reported it had seen documents last year showing she received a package worth more than $44,000 following mediation. Mathew Dearnaley